Alloy compositions and articles made therefrom



UNITED STATES PATENT OFFICE ALLOY COMPOSITIONS AND ARTICLES MADETHEREFROM No Drawing.

Application August 27, 1934, Serial No. 731.532. itenewed June 1, 1939 6Claims.

This invention relates as indicated to alloy compositions and articlesmade therefrom. and relates more particularly to ferrous alloys of thetype in which molybdenum and tungsten are important alloying elements.

In my prior Patent No. 1,937,334, dated November 28, 1933, there aredisclosed alloy compositions of the class in which molybdenum andtungsten are principal alloying elements and in which molybdenum andtungsten bear to each other a certain defined proportional relationship.The present invention is, in efiect, an extension of the teaching inthis prior patent, particularly with respect to variations in thecarbon, manganese, silicon, vanadium and chromium percentages.

It is among the objects of my invention to provide alloy compositions ofthe same general character as those disclosed in my above identifiedprior patent but which, due to variations in the amounts of certain ofthe alloying elements used. are better suited for certain purposes thanthe compositions defined in such prior patent. Other objects of myinvention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends. said invention,then, consists of the means hereinafter fully described and particularlypointed out in the claims.

The following description sets forth in detail some approvedcombinations of ingredients embodying my invention, such disclosed meansconstituting, however, but a few of the various forms in which theprinciple of the invention may be used.

My invention may be, as above indicated, stated in general terms ascomprising the discovery that certain variations in the composition orcompositions disclosed in my aforementioned prior patent result inalloys, particularly useful for certain purposes; more specifically thepresent invention relates to variations in the amounts of carbon,manganese, silicon, and chromium and to the omission of vanadium.

In accordance with my present invention, an alloy may contain thefollowing elements within the percentages given, viz:

Per cent Carbon 0. 15 to 1. 60 Manganese None to 2.00 Silicon None to 3.O Chromium None to 15. 00 Tungsten 0. 20 to 6.00 Molybdenum 0. 60 to 15.00 Cobalt None to 16.00

the remainder being substantially iron together with such other alloyingelements and impurities as are sometimes found in this type of alloycompositions.

Specific examples of vanadium-free compositions are as follows, viz:

'l'genotes below 30%.

the remainder being substantially iron together with such other alloyingelements and impurities as are sometimes found in this type of alloycompositions.

The importance of satisfactory alloy compositions in which vanadium isnot an essential ingredient, is potentially great especially so asvanadium is an expensive element, which is only produced in smallquantities in this country.

The above example is of particular interest, in that its raw materialcost is very low. When hardened at 2250 F. and tempered at 1040 F. itshowed a Rockwell hardness of C67 together with high strength. Cuttingtools such as drills showed excellent performance.

The type of steel having a low carbon content and in which vanadium andcobalt are not essential for certain uses has a potential usefulness inthe field of steels in which strength and toughness are of greaterimportance than cutting quality. It is particularly believed that thecarbon content of about 0.35% will produce steels which with proper heattreatment will have excellent strength and fatigue-resisting properties.The variety having a carbon content of 0.15% is expected to show someincrease in strength after appropriate heat treatment and isparticularly suitable for use as a carburizing steel.

The type of steel having a carbon content below 0.30% will probably finda field of usefulness, principally in the structural steels, in whichstrength is a more important characteristic than cutting quality. Thevaluable possibility is also recognized of carburizing this type ofsteel so that it may have a strong and tough core together with a hardwear-resisting case.

As previously indicated, compositions of the general class disclosedherein are similar to the general class disclosed in my prior Patent No.1,937,334 with respect to the tungsten and molybdenum content, i. e.,the amount of tungsten in the compositions may be broadly stated ascomprising about 5% to about 40% of the amount of molybdenum present. Asomewhat narrower range of proportional relationships between tungstenand molybdenum contemplates the use of tungsten in amounts from 10% to30% of the amount of molybendum present. The broad range of from 5% to40%. above referred to. may be conveniently divided into the followinggroups, viz.: 5% to 16%. 16% to 25% and 25% to 40%.

Attention is directed to the fact that certain of the examples includedin the foregoing description of my invention may be readily nitrlded.

As is well known to those familiar with the art, any specification for aparticular alloy composition must permit of certain variations due tothe fact that in making up the composition, it is extremely difiicult,if not impossible, to commercially produce a composition exactly like agiven specification. It is to be understood. therefore, that throughoutthe description and claims where I have used figures to denote definiteamounts and ranges, such amounts and ranges are to be construed toinclude the range of variations usually permissible in making up alloycompositions to given specifications.

It should be noted that where the term none" is used to denote theabsence of a particular element, or where an alloy composition isindicated as being free" from any element. the construction to be placedupon these terms is a commercial absence of the elements in question.Silicon. manganese. chromium, vanadium and cobalt may be considered ascommercially absent if they are present in amounts less than 0.05%.

Other modes of applying the principle of my invention may be employedinstead of the one explained, change being made as regards the materialsemployed. provided the ingredients stated by any of the following claimsor the equivalent of such stated ingredients be employed.

I, therefore. particularly point out and distinctly claim as myinvention:

1. A vanadium-free ferrous alloy composition, comprising:

Carbon From about 0.30% to about 1.60% Silicon From a trace to about3.00% Manganese From a trace to about 2.00 Chromium From a trace toabout 15.007} Molybdenum" From about 0.60% to about Tungsten From about5% to 40% of the amount of molybdenum presand the remainder beingsubstantially all iron.

2. A vanadium-free ferrous alloy composition, comprising:

amount of molybdenum present and the remainder being substantially alliron.

3. A vanadium-free ferrous alloy composition, comprising:

Carbon From about 0.30% to about 1.60%

Silicon From a trace to about 3.00;

Manganese From a trace to about 2.00 T

Chromium From a trace to about 15.00%

Molybdenum From about 0.60% to about Tungsten From about 16% to 25% ofthe amount of molybdenum present and the remainder being substantiallyall iron.

4. A vanadium-free ferrous alloy composition. comprising:

Carbon About 0.35% Manganese From a trace to about 0.30% Silicon From atrace to about 0.30% Chromium About 1.00% Tungsten About 0.30%Molybdenum About 1.20%

and the remainder being substantially all iron.

5. A vanadium-free ferrous alloy composition,

comprising:

Carbon About 0.75% Manganese About 0.70% Silicon About 1.60% ChromiumAbout 3.29% Tungsten About 1.59% Molybdenum About 7 23% and theremainder being substantially all iron.

6. A vanadium-free ferrous alloy composition,

comprising:

Carbon About 0.35% Manganese From a trace to about 0.30% Silicon From atrace to about 0.30% Chromium About 1.00% Tungsten About 0.15%Molybdenum About 0.60%

and the remainder being substantially all iron.

JOSEPH V. END/IONS.

